Date: Tue, 13 May 2003 19:53:25 +0200 From: "MH" <nomailnopsamhere.no> Subject: Re: Followup to RE: 1989 has battery drain
> There is still a TINY draw from the battery, like 5 millivolts, when > the car is off You mean there is a (current) drain of 5/1000 Amps - or a voltage drop ? = How did you measure this?=20 You took out the fuses and put the meter in series with the fuse = contacts, on the Amp range - that would be OK. If you had it on the mV range it indicated a voltage drop of 5mV over = the resistance of the fuse contacts (at whatever current was passing - = Ohms law; V =3D A * R) > But with a little clock and a flashing red light for > the radio, I figured this might explain it. The flashing red light is a LED (Light Emitting Diode). A typical LED = draws about 25 mA (at 1,75 V), that is a lot more than 5mA > Should this concern me? It didn't die overnight,=20 > so I finally got to enjoy a drive to work! =3D-) A new SAAB car battery has a capacity of at least 60 Ah (Amp.hours), = meaning it can supply 1 A for 60 hours, or 2 A for 30 hrs etc, so it = should be able to deliver 5mA for 12000 hrs (almost 1,5 year.....) > Thanks to you guys! I had never owned or used a voltmeter, so I really > feel like I've learned something! You will never stop learning... - voltage is measured paralel over whatever thingy you are checking, = unit is Volt (V) the meter in 'V' range has a very high internal = resistance. - current is measured in series with ....... unit is Ampere (A), the = meter in 'A' range has a very low internal resistance. ------------------------------------------- MH '72 97 '77 96 '78 95 '79 96 http://go.to/saab96